Sling bail

ABSTRACT

A sling bail adapted to hang from a lift crane hook or the like and suspend therefrom by means of chain legs a load lift magnet; said bail comprising a hook engaging eye portion formed integrally with a base portion which supports quick-disconnect chain links from which depend the magnet support chain legs. The invention features provision of improved means for detachably connecting the upper ends of the magnet support chain legs to the sling bail and supporting the sling bail in an upright condition when it is disconnected from the lift crane hook.

United States Patent Edward R. Belmke Lockport, N.Y.

Apr. 29, 1969 June 15, 1971 Columbus McKinnon Corporation Tonawanda, N.Y.

lnventor Appl. No. Filed Patented Assignee SLING BAIL 2 Claims, 6 Drawing Figs.

Int. Cl 86661/04 Field of Search 294/66, 67.4 A, 67.4 B, 74, 77, 81, 82, 65.5; 24/73, 73.05, 73.20, 73.85, 200, 201, 203; 248/317; 151/5 5 6] Referehces Cited I UNITED STATES PATENTS 1,540,055 6/1925 Chilton 151 5 3,009,727 11/1961 Jonesetal... 294/655 3,471,193 10/1969 Hayes 294 655 Primary Examiner- Evon C. Blunk Assistant Examiner-Johnny D. Cherry Attorney-Bean & Bean ABSTRACT: A sling bail adapted to hang from a lift crane hook or the like and suspend therefrom by means of chain legs a load lift magnet; said bail comprising a hook engaging eye portion formed integrally with a base portion which supports quick-disconnect chain links from which depend the magnet support chain legs. The invention features provision of improved means for detachably connecting the upper ends of the magnet support chain legs to the sling bail and supporting the sling bail in an upright condition when it is disconnected from the lift crane hook.

PATE N IED JUIH s an SHEET -1 BF 5 INVENTOR. :omuo R. GEHIYAE @mwwg A TTORNE Y5 PATENTED JUNE 5 I91:

SHEET 2 OF 5 INVENTOR.

EON/1RD RBEH/VKE A TTOR/VEY5 PATENTED JUN] 5 MI SHEET 3 BF 5 INVENTOR. EDWARD R. BEHA/KE PATEN TED JUN I 5 l97| SHEET 5 [1F 5 INVENTOR. 0 WARD R. BEHNKE A TTORNEYS SLING BAIL BACKGROUND OF THE INVENTION The present invention relates to sling bails and more particularly to bails of the type which are adapted to be hung from a lift crane hook and suspend therefrom a plurality of chain legs connected to a load lift magnet.

Sling bails of this chain type, which have come into wide use, suffer from one or more disadvantages including their inability to stand in an upright condition when disconnected from a lift crane hook and the difficulty with which maintenance may be performed thereon.

SUMMARY OF THE INVENTION The sling bail of the present invention is characterized as having a hook engaging eye formed integrally with a threelegged based portion from which magnet support chain legs may be suspended in such a manner as to minimize frictional wear due to twisting of the links forming the respective legs.

The chain legs'are connected to the bail by means ofjointer links which facilitate replacement of the chain legs when necessary and permit the bail to be supported in an upright position when it is disconnected from a lift crane hook. This feature of the present invention is particularly important in that it permits a crane operator to hook onto or unhook from the bail and thus the magnet without the need for a helper on the ground.

The bail of the present invention includes integrally formed safety lugs which bound the respective heads of the pivot pins employed to connect the joiner links to the bail and serve to permit assembly and locking in place of the pivot pins, while preventing possible dislodgment thereof during use due to contact with a broad surface object.

DRAWINGS The structure and mode of operation of the sling bail of the present invention will now be more fully described in the following detailed description taken with the accompanying drawings wherein:

FIG. 1 is a perspective view of the sling bail showing it suspended from a lift crane hook;

FIG. 2 is a perspective view similar to FIG. 1, but showing the sling bail supported on the ground;

FIG. 3 is a sectional view taken generally along the line 3-3 DETAILED DESCRIPTION Referring now to FIGS. 1 and 2, it will be seen that the sling bail of the present invention, which is generally designated as 1, includes an upper eye portion 2, which is preferably formed integrally with a base portion 3, having three identically configured, relatively radially extending legs 4, 4a, 4b. Legs 44b are, as best seen by reference to FIG. 5, equally spaced at 120 intervals about base portion 3 and positioned such that leg 4 is aligned with eye portion 2. Also, it will be noted upon referring to FIGS. 3-5 that the bottom surfaces of legs 4-41: are flattened and formed as continuations of the bottom surface of base portion 3, so as to define an expansive bail support. surface 3'.

Preferably, the cross-sectional area of the upperportion of eye portion 2 is enlarged, as indicated at 6 in FIGS. I and 4, so as to provide a relatively large bearing surface for engagement with hook 8 suitably carried by a crane or other lifting device, not shown.

In that legs 4-4!) are of identical construction, only leg 4 will be described in detail, it being understood that like parts of legs 4a, 4b will be designated by like numerals accompanied by the letters a and b, respectively.

Leg 4 is best shown in FIGS. 3 and 5 as being divided by an arcuate slot 10 into a pair of identically shaped flanges I], I2 having aligned apertures l3, 14 of hexagonal configuration. Oppositely facing outer surfaces of flanges ll, 12 are provided with a plurality of integral projections or lugs l5, 16, which are disposed in a relatively spaced annular relationship concentrically of apertures 13, 14, respectively.

A pivot pin 17 having a centrally disposed bearing surface portion 18 is provided with hexagonally configured head end portions 19, 20, which are adapted to be supportingly received one within each of apertures I3, 14 and cooperate therewith to prevent rotation of pin and thus wearing of flanges 11 and 12, which would otherwise result.

In accordance with the preferred embodiment of the present invention, pivot pin 17 is employed to support via bearing surface 18 a joiner link 22, which in turn serves to connect to bail l a conventional load lift magnet M, by a chain leg which are shown only in FIG. 6. However, it will be understood that pivot pin 17 may be employed to directly connect a magnet support chain leg to the bail.

By forming legs 4-4!) in the manner described, pivot pins 17-17!) are arranged so as to permit magnet M to be suspended from three relatively widely spaced points with the result that there is a tendency to constrain the magnet from relative rotation. Thus, the magnet is maintained in a correct plane and ware inducing twisting of the magnet support chain legs is minimized.

Pivot pin 17 is adapted to be releasably retained within apertures 13, 14 by suitable means, such as cotter pins 23, 24, which as indicated in FIG. 4, are receivable within apertures 25, 26 provided in head end portions 19, 20, respectively.

By referring to FIGS. 3 and 4, it will be understood that the spacing between adjacent lugs 15, I6 is sufficient to permit insertion and/or removal of cotter pins 23, 24 radially of pivot pin 17 when desired, and that the projecting lengths of such lugs is sufficient to prevent engagement of either head end portions 19, 20 or cotter pins 23, 24 by a broad surface object, not shown. Thus, this arrangement permits pins 17 to be readily removed for replacement purposes or to facilitate replacement of magnet support chain legs when ajoiner link 22 is not employed, while guarding against damage to or disassembly of either the cotter pins or pivot pins during use, should the sling bail be swung or dropped into engagement with a broad surface object.

.loiner link 22 is best shown in FIG. I and 3 as including complementary link halves 28, 29 each having at its opposite ends a pair of arms 30, 31 and a single arm 32, respectively, for cooperation as shown in FIG. 3. Arms 30-32 are provided with aligned openings, which, when registered permit insertion therewithin of a pin assembly indicated, generally as 33, which serves to pivotally join the link halves together. A more detailed discussion of the structure and mode of operation of pin assembly 33 may be had by referring to US Pat. No. 3,373,560. Joiner link construction employed in the practice of the present invention differs, however, from that developed in US. Pat. No. 3,373,560 in that upper link half 28, which bears upon pivot pin 17 within arcuate slot 10, is larger than conventionally sized lower link half 29, which is in turn adapted to support the uppermost link of a chain leg. Furthermore, the upper, inwardly facing surface of link half 28 is flattened, as at 34, so as to increase the bearing area between link half 28 and pin bearing surface I8 and thus reduce wear therebetween. Furthermore, flattened area 34 tends to prevent tilting of link half 28 in a direction axially of the pivot pin and thus minimizes the possibility of binding between upper link half 28 and leg flanges ll, 12.

It will be understood that by lengthening link half 28, arms 30-32 of link half 29 are permitted to freely swing about pin assembly 33, when joiner link 22 is suspended, as viewed in FIG. 3, while permitting the whole of the joiner link to be pivoted in a clockwise direction, also as viewed in FIG. 3,

without frictional interference with flanges l1, 12. When each of joiner links 22-22b are pivoted in the manner discussed with reference to link 22, such links are removed from beneath the bail and the bail permitted to be supported on the ground or like surface directly by expansive surface 3. ln normal operation, however, the bail when lowered by a crane operator, is adapted to be supported in an upright position by three point contact with the ground via links 2828b, which engage beneath legs 4-4b, as indicated in FIG. 2. In this connection, it will be apparent that the pivotal connections between the halves of the joiner links permit them to readily assume their positions shown in FIG. 2 in a controlled manner and thus minimizes wear and possible damage thereto should the bail be dropped or lowered in haste.

lclaim:

l. A sling bail of the type adapted to be hung from a lift crane hook and suspend therefrom by chain legs, a load lift magnet, said bail having in combination:

an eye portion adapted to receive said hook;

a base portion formed integrally with said eye portion, said base portion having three legs extending radially therefrom and arranged at equally spaced intervals peripherally thereof, each said leg being divided radially thereof by a slot into a pair of leg flanges, said leg flanges of each said pair having aligned apertures extending through facing surfaces thereof, said leg flanges of each said pair having projections on oppositely facing surfaces thereof, said projections being disposed in a relatively spaced annular relationship concentrically of said aperlures;

plurality of pivot pins provided one in association with each said leg, each said pin including head end portions and an intermediate bearing surface portion, said head end portions being removably received one within each of said aligned apertures and cooperating therewith to prevent relative rotational movement of said pin about the axis thereof with respect to said leg flanges,

joiner links provided one in association with each said pin,

each said joiner link including complementary upper and lower link halves and means to removably join said link halves for relative pivotal movement, said upper link half being freely receivable within said dividing slot for engagement with said pin bearing portion, said lower link being adapted to releasably support one of said chain legs, said upper link being dimensioned such that, when supported by said pin bearing portion, said link joining means is disposed below the bottom surface of said leg thereby permitting said lower link to be pivoted into underlying supporting engagement with said leg bottom surface.

2. A sling bail according to claim 1, wherein the inwardly facing surface of said upper link disposable in supporting engagement with said pin bearing portion is flattened in a direction axially of said pin, so as to increase the bearing area therebetween. 

1. A sling bail of the type adapted to be hung from a lift crane hook and suspend therefrom by chain legs, a load lift magnet, said bail having in combination: an eye portion adapted to receive said hook; a base portion formed integrally with said eye portion, said base portion having three legs extending radially therefrom and arranged at equally spaced intervals peripherally thereof, each said leg being divided radially thereof by a slot into a pair of leg flanges, said leg flanges of each said pair having aligned apertures extending through facing surfaces thereof, said leg flanges of each said pair having projections on oppositely facing surfaces thereof, said projections being disposed in a relatively spaced annular relationship concentrically of said apertures; a plurality of pivot pins provided one in association with each said leg, each said pin including head end portions and an intermediate bearing surface portion, said head end portions being removably received one within each of said aligned apertures and cooperating therewith to prevent relative rotational movement of said pin about the axis thereof with respect to said leg flanges, joiner links provided one in association with each said pin, each said joiner link including complementary upper and lower link halves and means to removably join said link halves for relative pivotal movement, said upper link half being freely receivable within said dividing slot for engagement with said pin bearing portion, said lower link being adapted to releasably support one of said chain legs, said upper link being dimensioned such that, when supported by said pin bearing portion, said link joining means is disposed below the bottom surface of said leg thereby permitting said lower link to be pivoted into underlying supporting engagement with said leg bottom surface.
 2. A sling bail according to claim 1, wherein the inwardly facing surface of said upper link disposable in supporting engagement with said pin bearing portion is flattened in a direction axially of said pin, so as to increase the bearing area therebetween. 